Help me accurize my 6920

[Fatorangecat]

I'm new to the world of ARs and could use some experienced guidance. I have a Colt 6920 with an ACOG TA11F in an ADM mount. I would like to utilize the ACOG BDC and according to Trijicon an 18" barrel would be best. I want the rifle to be as accurate as possible without sacrificing reliability or being excessively heavy. I spend a lot of time on the ground shooting off a bipod but would like a rifle compact and light enough to act as a carbine.

Now for the questions...I have read hours and hours of information on the forum. At one end of the spectrum are guys saying a barrel and a trigger are all you need for precision and at the other end of the spectrum are guys reengineering the entire system. What components should I upgrade on a 6920 to make a reliable precision carbine? I'm going to avoid terms like SPR or DMR as they seem to mean different things to different people but I want a tactical/precision carbine. Any advice would be appreciated. At this point I have found so much information I'm not sure where to start.

 

[nuclear_shooter]

I'm new to the world of ARs and could use some experienced guidance. I have a Colt 6920 with an ACOG TA11F in an ADM mount. I would like to utilize the ACOG BDC and according to Trijicon an 18" barrel would be best. I want the rifle to be as accurate as possible without sacrificing reliability or being excessively heavy. I spend a lot of time on the ground shooting off a bipod but would like a rifle compact and light enough to act as a carbine.

Now for the questions...I have read hours and hours of information on the forum. At one end of the spectrum are guys saying a barrel and a trigger are all you need for precision and at the other end of the spectrum are guys reengineering the entire system. What components should I upgrade on a 6920 to make a reliable precision carbine? I'm going to avoid terms like SPR or DMR as they seem to mean different things to different people but I want a tactical/precision carbine. Any advice would be appreciated. At this point I have found so much information I'm not sure where to start.

I guess the first thing would be to float the handguard and probably ditch the gas block for an adjustable one. If your interested in an 18" you could also do that when you change the handguards.

 

[Fatorangecat]

I'm thinking 15" NSR with an 18" WOA mid length SPR barrel but I haven't given much consideration to an adjustable gas block.

 

[akhntr]

Put on that free float handguard, (pay an expert to do it) and spend 200 for a high quality trigger set around 3-5 lbs. Those two things made my factory 6920 shoot amazing with factory barrel etc. Start there, you will change more later. That's the fun of an AR rifle. Like Leggos for big guys.

 

[Cobracutter]

Why not just build a new gun? Don't fuck up a 6920 trying to chase small groups.

With an ACOG, that gun already shoots better than you with decent ammo. You, the glass and the trigger are more of a limiting factor than the weapon.

You use terms like Accuracy, reliability, ect..... what do you define them as? They all mean different things to different people. There is no free lunch, quality costs $$ and the more precision oriented an AR is, all things being equal, the more unreliable it is.

 

[ORD]

The biggest items that contribute to the accuracy of any AR-platform rifle are (VERY generally): a) a quality match trigger that is crisp, clean, and consistent (regardless of the total weight of pull, type, etc.); b) a quality barrel capable of delivering accurate performance in and of itself; c) a quality free-floated handguard/rail system; and d) a shooter that can competently operate the rifle/carbine (most often overlooked portion of the accuracy equation).

For your 6920...those things will all have to be addressed in order for you to get the most out of the carbine in terms of accuracy potential.

So...first things first...the ACOG. While BDC's have their place, they will ONLY work under an extremely specific set of conditions, including but not limited to muzzle velocity (the biggie), a specific ammo at a specific MV and under environmental conditions (elevation, heat, humidity, etc.). Furthermore, they are also based on the specific mount (the TA51 with respect to your ACOG which you have since changed out to the ADM), height over bore, etc.

With that in mind, the TA11F is based on a 14.5" barreled M4 Carbine firing M855 (62gr) traveling at a MV of 2,970fps with a G1 BC of 0.304 and a height over bore of 2.5" which is achieved with the TA51 mount on an M4 flattop receiver. Now, what specific ammo/bullet/MV/etc. you are running (at least running the majority of the time) will ultimately determine how close (or how far off) the TA11F BDC will be for you at any given range along the BDC scale. Barrel length is but a small part of the equation so I wouldn't be set on an 18" barrel unless that just happens to give you the "combo" of factors you need to get closest to the BDC as per Trijicon (not knowing your ammo or any other pertinent specifics, its a guess as to what may/may not work well for you). The differences between what your rifle is spitting out versus what the BDC gives you can be anywhere from very close (and inch or so) to a good long ways off.

For "precision" work...I'd gladly skip the ACOG and opt for a low-powered, variable magnification (1-4x or 1-6x) standard rifle optic with a quality mil-based or moa-based reticle (just match the reticle to the scope's adjustment type) that you can use hold-overs on if you really must or otherwise dial your elevation adjustments to get on target.

As to the barrel...I wouldn't get to caught up on a specific length, especially a longer, 18" barrel. While 18" is a great all-around barrel choice for a 5.56/.223 AR, it is getting LONG for a carbine and will add forward weight, perhaps unnecessarily, to your carbine even if you opt for a lighter weight contour barrel. You can get quality, match barrels in lengths from 14.5" to 18" without too much trouble, so it really all comes down to what you want/need at the end of the day.

As to the FF tube/handguard...the sky is the limit here. Find one you like and that offers features/functions you deem desirable and go for it.

As to triggers...I am a big proponent of the Geissele two-stage triggers which I have used almost exclusively for the last couple years. They offer a ton of different options based on individual shooter requirements, but I would look to the non-adjustable units like the SSA or even the SSA-E (lighter overall weight of pull) or SD-E for your purposes. If you'd prefer a single-stage trigger, there are a lot of quality options, including drop-in units like those from Timney and Wilson Combat's TTU (both single and two-stage available), as well as JP Enterprises.

At some point in time, you may be better served just building a complete upper to work with your 6920 lower and keep the 6920 upper "as is". Your money...your rifle...your call.

 

[Fatorangecat]

ORD I was under the impression the TA11F was based on M855 in a 14.5" barrel as well but Trijicon tells me it's M855 at 3050fps. That seems to correspond to an 18" barrel but I have no way of verifying that personally. I understand there are a lot of variables at play with BDC and it is not my first choice in an optic but I acquired the M4/ACOG/mount as a package for an awesome trade. For what I want to do with the rifle I don't think it's a bad combo to start with.

 

[MarshallDodge]

Why not just build a new gun? Don't fuck up a 6920 trying to chase small groups.

With an ACOG, that gun already shoots better than you with decent ammo. You, the glass and the trigger are more of a limiting factor than the weapon.

You use terms like Accuracy, reliability, ect..... what do you define them as? They all mean different things to different people. There is no free lunch, quality costs $$ and the more precision oriented an AR is, all things being equal, the more unreliable it is.

Very good points.

I have a Bravo Company 16" midlength upper that will hover around 2" at 100 with the plastic handguards resting in my sons hands laying prone. Stock GI trigger and an Aimpoint scope. Ammo was 55 FMJ Hornady bullets over some ancient 4895 powder. For a chrome lined bore in a defensive rifle I am more than happy with this.

My other gun is has a 16" midlength Sabre Defense SS 1:8 with a VTAC free float handguard. Tuned GI trigger and scope is a 1-4 Vortex Razor. It will shoot 3/4" on a good day with 75 grain reloads.

Both have been very reliable with the only issues being ammo related. Both of them have 5.56 chambers. If you get away from that then you are asking for reliability issues.

If you want better accuracy then start with match ammo or reloads. Most of the military ball ammo on the market is lacking in the precision department.

 

[ORD]

ORD I was under the impression the TA11F was based on M855 in a 14.5" barrel as well but Trijicon tells me it's M855 at 3050fps. That seems to correspond to an 18" barrel but I have no way of verifying that personally. I understand there are a lot of variables at play with BDC and it is not my first choice in an optic but I acquired the M4/ACOG/mount as a package for an awesome trade. For what I want to do with the rifle I don't think it's a bad combo to start with.

I always thought that Trijicon's claimed velocities were a little on the "wishful" side of things, but I can't honestly see getting 3000fps+ out of 62gr from a 14.5" barreled M4 and frankly, even the 2970fps is probably on the wishful side of things. The 2970fps is the FM figure...which also means its probably wrong too!

The only way you'll know where you are with your particular ACOG is to actually shoot it at distance using your pet load/ammo and using the BDC and then record the values you observe for future use (+/- x-MOA or mils at a, b, c, d, etc.-range). Otherwise...its purely academic at this point!

 

[Fatorangecat]

Not to sound like a Jerk because I really do appreciate everyone taking time to comment but we have covered the spectrum. We have gone from "my rifle and optic will outshoot me" to "not having enough optic" and "building a whole new rifle". I understand you have to pay to play, I have more wrapped up in my bolt action than my car but I'm not building man jewelry. What is the mechanical difference between squaring my receiver and installing a matched bolt and barrel compared to a billet upper and an aftermarket BCG? The 6920 is by most accounts a good weapon with quality components as well as the ACOG. I guess I'm trying to find the point of diminishing returns.

 

[Fenix Mike]

Either just toss a free float rail on it, or build a new upper and sell/store the colt. I stuck a Geissele mk4 13 inch rail on a colt 6920 with a run of the mill 4.5 lb trigger and it shoots sub moa just fine with good ammo, but others have told you the limiting factor is how you equip it and your shooting ability. If you want to punch further out, build a new upper with a 18-20 inch match barrel, but for sub 500 yard stuff that colt barrel is fine (many people, including myself, take it out much further). Also consider just buying a 6940 upper which has the monolithic upper and free float rail from the factory, it's just not very long. There are tons of threads about how accurate the 6940 is out of the box.
And also like others said, don't destroy a 6920 upper just to reuse the $100 upper, build another or just do a rail

 

[tickled pink]

I put a Geissele SSA-E trigger in my Colt LE6920 M4 which cut my groups down greatly, but not accurate enough for me. I ended up ordering a complete White Oak Armament 18" varmint upper with a 1 in 7" twist and having it full length Fluted to save some weight. I am hoping it will shoot less than 1/2" groups at 100 yds. with my reloads.

White Oak Armament

It will look similar to this one.

<iframe width="560" height="315" src="//www.youtube.com/embed/4tx-ZzQIolw" frameborder="0" allowfullscreen></iframe>

 

[Tangodown911]

The biggest items that contribute to the accuracy of any AR-platform rifle are (VERY generally): a) a quality match trigger that is crisp, clean, and consistent (regardless of the total weight of pull, type, etc.); b) a quality barrel capable of delivering accurate performance in and of itself; c) a quality free-floated handguard/rail system; and d) a shooter that can competently operate the rifle/carbine (most often overlooked portion of the accuracy equation).

For your 6920...those things will all have to be addressed in order for you to get the most out of the carbine in terms of accuracy potential.

So...first things first...the ACOG. While BDC's have their place, they will ONLY work under an extremely specific set of conditions, including but not limited to muzzle velocity (the biggie), a specific ammo at a specific MV and under environmental conditions (elevation, heat, humidity, etc.). Furthermore, they are also based on the specific mount (the TA51 with respect to your ACOG which you have since changed out to the ADM), height over bore, etc.

With that in mind, the TA11F is based on a 14.5" barreled M4 Carbine firing M855 (62gr) traveling at a MV of 2,970fps with a G1 BC of 0.304 and a height over bore of 2.5" which is achieved with the TA51 mount on an M4 flattop receiver. Now, what specific ammo/bullet/MV/etc. you are running (at least running the majority of the time) will ultimately determine how close (or how far off) the TA11F BDC will be for you at any given range along the BDC scale. Barrel length is but a small part of the equation so I wouldn't be set on an 18" barrel unless that just happens to give you the "combo" of factors you need to get closest to the BDC as per Trijicon (not knowing your ammo or any other pertinent specifics, its a guess as to what may/may not work well for you). The differences between what your rifle is spitting out versus what the BDC gives you can be anywhere from very close (and inch or so) to a good long ways off.

For "precision" work...I'd gladly skip the ACOG and opt for a low-powered, variable magnification (1-4x or 1-6x) standard rifle optic with a quality mil-based or moa-based reticle (just match the reticle to the scope's adjustment type) that you can use hold-overs on if you really must or otherwise dial your elevation adjustments to get on target.

As to the barrel...I wouldn't get to caught up on a specific length, especially a longer, 18" barrel. While 18" is a great all-around barrel choice for a 5.56/.223 AR, it is getting LONG for a carbine and will add forward weight, perhaps unnecessarily, to your carbine even if you opt for a lighter weight contour barrel. You can get quality, match barrels in lengths from 14.5" to 18" without too much trouble, so it really all comes down to what you want/need at the end of the day.

As to the FF tube/handguard...the sky is the limit here. Find one you like and that offers features/functions you deem desirable and go for it.

As to triggers...I am a big proponent of the Geissele two-stage triggers which I have used almost exclusively for the last couple years. They offer a ton of different options based on individual shooter requirements, but I would look to the non-adjustable units like the SSA or even the SSA-E (lighter overall weight of pull) or SD-E for your purposes. If you'd prefer a single-stage trigger, there are a lot of quality options, including drop-in units like those from Timney and Wilson Combat's TTU (both single and two-stage available), as well as JP Enterprises.

At some point in time, you may be better served just building a complete upper to work with your 6920 lower and keep the 6920 upper "as is". Your money...your rifle...your call.

Right on! Man I commend you for being able to type all that. The OP got a bonus there. Back in my early days I had to use the search feature.

OP- man just build you what you want from the ground up. I'm with the other guys. Don't FOOK up a 6920. Enjoy it for what it is.

 

[Fatorangecat]

I appreciate all the good advice. I'm thinking Geissele trigger, Geissele rail, White Oak barrel for the summer. I will pick up a billet upper/lower and another bolt carrier and put the 6920 back together. It is a nice rifle and I would hate to waste a good barrel assembly.

 

[997/2man]

As others have said, you are too far away from where you want to be, with what you have. Start a new, purpose built rifle.


It will be cheaper, you will be ahead. The 6920 is a fine little carbine, Colt name, don't make it a Franken rifle.

You should have sold it a year ago, when prices were astronomical.

Check the For Sale Section, you would be surprised what pops up.

Either way, good luck.

 

[JimBianchi]

Two best things I ever did to improve the accuracy of my AR is a great trigger (Timney 3#) and match ammo.

Most of my AR's will do 2 or 3 inches at 100y with regular ammo.

One of my guns will do 1.25 MOA (so far all the way out to 400y, farther maybe) with 69g grade match and another will do 1 MOA with two types of 77gn match ammo.

Expensive ammo solved a lot of issues.

Free floating the handguard made zero different with this particular gun. (but I prefer the free float any ways.)

 

[Sterling Shooter]

Not to sound like a Jerk because I really do appreciate everyone taking time to comment but we have covered the spectrum. We have gone from "my rifle and optic will outshoot me" to "not having enough optic" and "building a whole new rifle". I understand you have to pay to play, I have more wrapped up in my bolt action than my car but I'm not building man jewelry. What is the mechanical difference between squaring my receiver and installing a matched bolt and barrel compared to a billet upper and an aftermarket BCG? The 6920 is by most accounts a good weapon with quality components as well as the ACOG. I guess I'm trying to find the point of diminishing returns.

With your equipment, good hits on the E target are easy to 600 meters shooting Mk262, by any shooter able to properly execute the two firing tasks, and correctly favor for wind. By this I mean a shooter who knows how to properly point the rifle with consistent sight alignment and pull the trigger without moving the rifle utilizing smooth trigger control, supporting those tasks by transferring the stability of the ground into a steady position and correctly estimating the effect of wind. Match conditioning your gun would perhaps get a better result on a decimal target by a novice shooter using the match conditioning as a substitute for marksmanship proficiency. Match conditioning would also assure a better result for the accomplished shooter. So the question is what do you need to do if anything to get the job done. Match conditioning, as well as training would of course assure the best result.

 

[Fatorangecat]

I'm pretty sure I'm not the first person to want a match barrel on a Colt carbine. I see guys all over this forum with RRA, DPMS, etc with high end barrels, is that a waste too? I want a carbine that is capable of a bit more mechanical accuracy than a chrome lined M4 barrel with M4 handguards. I don't want a bench rifle. I already have one. What everybody else is seeing as a waste of a 6920, I'm seeing as a 6920 with a match barrel and trigger.

 

[Sterling Shooter]

I'm pretty sure I'm not the first person to want a match barrel on a Colt carbine. I see guys all over this forum with RRA, DPMS, etc with high end barrels, is that a waste too? I want a carbine that is capable of a bit more mechanical accuracy than a chrome lined M4 barrel with M4 handguards. I don't want a bench rifle. I already have one. What everybody else is seeing as a waste of a 6920, I'm seeing as a 6920 with a match barrel and trigger.

As I said in my previous post, you can match condition your rifle and get some marksmanship training to assure the best result, would it not?

 

[Fatorangecat]

As I said in my previous post, you can match
condition your rifle and get some marksmanship training to assure the best result, would it not?

That is exactly what I'm going to do. I don't see a need to build a new rifle. Education is a solid recommendation for anything.

 

[MosesTheTank]

Tweaking your 6920

I was a little disappointed with my 6920 as it came out of the box so I changed components one at a time and am now very happy with it. Mostly repeating what others have said, get a free float tube. Although not on this rifle, my favorite is the Troy Alpha VTAC. For triggers I only use Timney's, most of them at 3lbs. If you ever have to take the trigger out it is much easier to do so with a self-contained unit, especially if you are tired and have cold fingers. All my ARs have a Syrac adjustable gas block. They are easy to adjust and make a huge difference. Finally, get a good muzzle brake. After lots of experimentation I just use the Surefires. They don't require tuning and have done wonders for my double taps. Accuracy is much better because of better trigger control and reduced recoil impulse. A mid length gas system would help but I have no need change out the barrel as it does everything I need for this particular rifle. I agree with the poster who said to have a competent gunsmith do the work. But I would add to that to hire one who is willing to show you how it's done. Knowing your rifle and how to tweak it is half the fun and could be worth its weight in gold in a pinch.

Please report back with your results.

 

[leadbullet]

Simple, new barrel, hand guard, trigger group, bolt carrier group, or just buy a JP.
Cheers

 

[mtrmn]

I have yet to work with an AR that is NOT capable of MOA or less at 100 yds with the right ammo that the gun likes. Put a decent trigger in it and start reloading. Work up a load the gun likes and the factory bbl will do fine. Just my opinion, but you don't have to rebuild the thing to get good accuracy out of it. It is rare to find an AR that will attain peak accuracy with factory ammo IME.

 

[Matno]

I built my own, but my dad has a colt that does quite well with the standard barrel. For mine, I went with a lightweight 16" melonite barrel. Couldn't be happier. Shoots sub MOA and theoretically has both a longer barrel life and slightly increased muzzle velocity over chrome lined. Also have an SSA-E trigger and a free float handguard. Like the trigger so much that I'll be getting one for my AR-10 soon.

 

[MistWolf]

THINGS THAT WILL IMPROVE THE MECHANICAL ACCURACY OF AN AR
1) Quality barrel, including chamber. It doesn't matter if the barrel is made of stainless steel or chromoly steel. However, due to the way the steels wear, the chromoly barrel loses accuracy gradually and the stainless steel barrel will lose it all at once. Some accuracy is generally lost to chrome lining, say about a half MOA. Wylde chambers give good results

2) Matching the bolt to the barrel. There is a headspace range that generally improves the consistency and roundness of groups from a 5.56/223 AR

3) Free float tube. Some ARs will group better with a free float tube but not all. However, the free float tube will keep pressure from resting the handguard on something or when using a bipod from shifting point of impact

A trigger does NOT affect mechanical accuracy. It only makes it easier or harder for the shooter to make a good shot.

Don't waste your money on billet receivers. A receiver cut from a billet instead of a forging, or from 6061 instead of 7075 isn't as stiff. You will want a stiff upper receiver for best consistency. Use a receiver made from a 7075 forgings. The VLTOR MUR upper is stiffer than a standard upper and both the VLTOR MUR and the new BCM upper are made to higher quality standards.

I don't say you have to do all of the above to make your 6920 better. Take a look and see what would be practical for you and try. Maybe changing to a free float tube and installing an SSA trigger will give you what you want. But if you're going to rebarrel your upper, I agree with those that suggest getting another complete upper instead

 

[Fatorangecat]

I was a little disappointed with my 6920 as it came out of the box so I changed components one at a time and am now very happy with it. Mostly repeating what others have said, get a free float tube. Although not on this rifle, my favorite is the Troy Alpha VTAC. For triggers I only use Timney's, most of them at 3lbs. If you ever have to take the trigger out it is much easier to do so with a self-contained unit, especially if you are tired and have cold fingers. All my ARs have a Syrac adjustable gas block. They are easy to adjust and make a huge difference. Finally, get a good muzzle brake. After lots of experimentation I just use the Surefires. They don't require tuning and have done wonders for my double taps. Accuracy is much better because of better trigger control and reduced recoil impulse. A mid length gas system would help but I have no need change out the barrel as it does everything I need for this particular rifle. I agree with the poster who said to have a competent gunsmith do the work. But I would add to that to hire one who is willing to show you how it's done. Knowing your rifle and how to tweak it is half the fun and could be worth its weight in gold in a pinch.

Please report back with your results.

I finally made it to a real computer and saw your Colt. that is a really cool setup.

 

[Cobracutter]

I'm pretty sure I'm not the first person to want a match barrel on a Colt carbine. I see guys all over this forum with RRA, DPMS, etc with high end barrels, is that a waste too? I want a carbine that is capable of a bit more mechanical accuracy than a chrome lined M4 barrel with M4 handguards. I don't want a bench rifle. I already have one. What everybody else is seeing as a waste of a 6920, I'm seeing as a 6920 with a match barrel and trigger.

Yea, if the meat bucket behind the gun doesn't have the knoweledge, training and experince, its a waste.

Its also generaly unwise to put quality parts on shitty guns when you can build a quality gun from the ground up for equal money (and sometimes cheaper)

 

[Cobracutter]

That is exactly what I'm going to do. I don't see a need to build a new rifle. Education is a solid recommendation for anything.

And to be honest, an M4 or 6920 is not the best rifle to learn on. A 20" AR , m16 or similar is a much better tool for teaching and delvoping your skills. Longer sight radius, heavier(more stability) solid stock that is easier to shoot nose to charging handle (or whatever repeatable cheek weld you use).

Buy yourself a Colt Match rifle or WOA Service rifle and go shoot some highpower matches. That will give you MORE than enough training and experince to become a great shooter. Appleseed is also another solid program that will cost way less and develop your marksmanship skills.

A m4 tpye gun with its shorter sight radius (less forgiving in shooter error), lighter weight and collapsable stock is going to be much harder to develop consitant skills. Once you get the full rifle compentency down, you can move on to other style guns, and will have a better understanding of their shortcomings, allowing you to address and minimize them.

 

[samnev]

And to be honest, an M4 or 6920 is not the best rifle to learn on. A 20" AR , m16 or similar is a much better tool for teaching and delvoping your skills. Longer sight radius, heavier(more stability) solid stock that is easier to shoot nose to charging handle (or whatever repeatable cheek weld you use).

Buy yourself a Colt Match rifle or WOA Service rifle and go shoot some highpower matches. That will give you MORE than enough training and experince to become a great shooter. Appleseed is also another solid program that will cost way less and develop your marksmanship skills.

A m4 tpye gun with its shorter sight radius (less forgiving in shooter error), lighter weight and collapsable stock is going to be much harder to develop consitant skills. Once you get the full rifle compentency down, you can move on to other style guns, and will have a better understanding of their shortcomings, allowing you to address and minimize them.

I agree with Cobracutter. Sell the 6920 and get the Colt H3 Enhanced 6721 Target model. But on second thought since you already have a target AR I would go for an SR 15 or a comparable Noveske AR. Then you ail have what you want without having to sweat a rebuild. The cost will be higher than all the upgrades you will need to do on the 6920 but it's unlikely if you ever sell it you will recover the money you put in it. I went through a similar process thinking about upgrading a Remington 5R. But finally decided to sell it and bought and AIAW and have never regretted it. Good luck in your quest.

 

[Sterling Shooter]

And to be honest, an M4 or 6920 is not the best rifle to learn on. A 20" AR , m16 or similar is a much better tool for teaching and delvoping your skills. Longer sight radius, heavier(more stability) solid stock that is easier to shoot nose to charging handle (or whatever repeatable cheek weld you use).

Buy yourself a Colt Match rifle or WOA Service rifle and go shoot some highpower matches. That will give you MORE than enough training and experince to become a great shooter. Appleseed is also another solid program that will cost way less and develop your marksmanship skills.

A m4 tpye gun with its shorter sight radius (less forgiving in shooter error), lighter weight and collapsable stock is going to be much harder to develop consitant skills. Once you get the full rifle compentency down, you can move on to other style guns, and will have a better understanding of their shortcomings, allowing you to address and minimize them.

I hope the OP takes this advice. Just the longer sight radius alone as on the A2,A3,or A4 better assures an in-focus front sight, which is essential for recognition for where the barrel is pointed.

 

[Fatorangecat]

Why is it on this and every other shooting forum when you ask a question everybody assumes your green? I am not new to shooting and I'm not new to precision shooting. I said I was new to ARs. I did not ask about building a target rifle or about learning fundamentals. I asked a question about tuning more accuracy out of a carbine with a TA11F. The combination of a carbine and an ACOG alone should be enough to give you a clue. Read the OP...I asked a specific question and qualified the question to avoid the rants on fundamentals and tangential crap about match rifles.

 

[dangerranger6100]

I would build a whole new upper if you're going to replace the barrel. The complete upper will be about $300 more than replacing all the parts on your 6920, plus you get to keep the 6920 together.

If you're replacing the barrel and handguard, you would only need an upper receiver and parts ($110), muzzle device ($15-75), and gas block ($35-70), and BCG ($125)

 

[Tangodown911]

Why is it on this and every other shooting forum when you ask a question everybody assumes your green? I am not new to shooting and I'm not new to precision shooting. I said I was new to ARs. I did not ask about building a target rifle or about learning fundamentals. I asked a question about tuning more accuracy out of a carbine with a TA11F. The combination of a carbine and an ACOG alone should be enough to give you a clue. Read the OP...I asked a specific question and qualified the question to avoid the rants on fundamentals and tangential crap about match rifles.

Your low post count has doomed you

 

[ORD]

Why is it on this and every other shooting forum when you ask a question everybody assumes your green? I am not new to shooting and I'm not new to precision shooting. I said I was new to ARs. I did not ask about building a target rifle or about learning fundamentals. I asked a question about tuning more accuracy out of a carbine with a TA11F. The combination of a carbine and an ACOG alone should be enough to give you a clue. Read the OP...I asked a specific question and qualified the question to avoid the rants on fundamentals and tangential crap about match rifles.

It is your carbine and ultimately, whatever you do, you'll have to live with it and the results you achieve. You've received a ton of good advice to date in this thread...only you can ultimately decide what's best for YOU and what you want/need out of the rifle with any upgrades, whether a new complete upper receiver group is warranted/more cost-effective in the long-run, etc.

If you are trying to save money or step-by-step upgrade to see how it goes before going "all in," I'd start with the trigger and the handguard upgrades and then, once you get everything back together, decide if the accuracy/function improvements at that point warrant a new barrel (arguably the largest portion of your upgrade cost) and go from there. Again...your carbine...your money...your call!

 

[Fatorangecat]

It is your carbine and ultimately, whatever you do, you'll have to live with it and the results you achieve. You've received a ton of good advice to date in this thread...only you can ultimately decide what's best for YOU and what you want/need out of the rifle with any upgrades, whether a new complete upper receiver group is warranted/more cost-effective in the long-run, etc.

If you are trying to save money or step-by-step upgrade to see how it goes before going "all in," I'd start with the trigger and the handguard upgrades and then, once you get everything back together, decide if the accuracy/function improvements at that point warrant a new barrel (arguably the largest portion of your upgrade cost) and go from there. Again...your carbine...your money...your call!

Your right this thread does have a ton of good information. I had no idea about the Syrac adjustable gas blocks. The detent is an awesome feature and I will be picking one up for this rifle regardless whether I decide to get a match barrel or not. At this point I'm going to send some money to Geissele, a good trigger and a MK4 rail. I just wish I could have a conversation without the condescending rants. Not that I really care but its just unnecessary.

 

[ORD]

I just wish I could have a conversation without the condescending rants. Not that I really care but its just unnecessary.

Welcome to the Internet!

I think you've got a good start with the Geissele trigger and handguard upgrade, along with the an adjustable block. You might also have a look at the SLR Rifleworks newest "Sentry" blocks which are excellent products and offer some advantages over the Syrac in my experience (nothing wrong with the newer Gen 2 Syrac blocks...I just prefer the SLR design myself).

Worst case scenario...if you get into this whole "upgrade" project and decide you are still wanting...its easy to put everything back on the 6920 to return it to its original state and then use the "'upgrade" components to build out a different rifle that may better serve you in the long run.

Good luck and God speed! Be sure to keep an update going on your progress (whether in this thread or another, new one).

 

[Sterling Shooter]

The only modification I've ever made to any 6920 has been the insertion of an aperture valve in the large low visibility/smoke/night aperture. This gets me down to about 036 for a sharp front sight as well as a well defined target. My accuracy improves as I understand better where the barrel is pointed and I understand when the relationship between sight and target is consistent. My valve was produced by Bill Merchant and I think may be available from Brownells. Using it I can get better hits than with the ACOG since I can not as easily recognize consistent sight alignment with the ACOG thus perspective of aim issues preclude the best results.

One thought about the ACOG. Most of my experience is with the field expedient TA31F. I have seen it on M4's as well as M16A4's shot with M193, M855, and Mk262. All of these combinations can be made to work for a BDC function if the sight is zeroed at the long end. Then, error is greatest at SR where it is not an issue when using a center mass hold on the E type target.

 

[Sterling Shooter]

Why is it on this and every other shooting forum when you ask a question everybody assumes your green? I am not new to shooting and I'm not new to precision shooting. I said I was new to ARs. I did not ask about building a target rifle or about learning fundamentals. I asked a question about tuning more accuracy out of a carbine with a TA11F. The combination of a carbine and an ACOG alone should be enough to give you a clue. Read the OP...I asked a specific question and qualified the question to avoid the rants on fundamentals and tangential crap about match rifles.

Since all shooting is the same, that's to say, the idea is to properly point the rifle and pull the trigger without disturbing aim, the M4 with whatever sight would be seen like any other gun/sight combination, meaning what would improve performance on one concept would likely improve performance on another. So, rather than appreciate advice that complements what you seek to know within your imposed limitations why not consider as well experiences outside your arena. After all it is you that asked for advise, and consideration of advice beyond your scope might expand your knowledge to see alternative solutions which may assure a more satisfying outcome.

 

[Fatorangecat]

That is a great piece of advice. Work long range in and accumulate the margin of error on the less noticeable end.

 

[mtrmn]

I own several POS ARs. I enjoy trying to make them shoot/perform better without building a whole new gun. The best bang for the buck I've found is a good trigger and reloading ammo tailored to the gun.

 

[Raider Power]

I've got a pretty similar setup, 6920 with an ACOG. With this setup, ive got a quick handling accurate carbine that does everything I need the rifle to do. I use mine to mostly shoot varmints (mostly coyotes and hogs) and have used the bdc out to about 500 yards for larger targets (55 gallon drum size). I don't see well enough to use a 4x optic on much smaller targets at that kind of range. I don't think I need more accuracy for my uses which seem to be reasonably inline with what the OP wants to do.

I've bounced thoughts of changing things around since I got it but haven't ever made the commitment to do so. It shoots damn well for what it is, so I can't bring myself to change anything. If I did want to make changes, a new trigger and a free float handgaurd would be the only things I changed for this rifle.

If I wanted something more accurate or with more reach than what I described above, I'd probably build a purpose built rifle from the ground up. As it sits, my 6920 fits my need for a quick handling accurate rifle perfectly.